Imaging lung cancer by scintigraphy with Indium 111-labeled F(ab')2 fragments of the anticarcinoembryonic antigen monoclonal antibody FO23C5.

BACKGROUND: Anticarcinoembryonic (CEA) monoclonal antibodies are able to react specifically with the antigen and have the potential for the detection of CEA-bearing tumors. METHODS: The authors photoscanned with indium 111 (111In)-labeled F(ab')2 fragments of the murine CEA monoclonal antibody FO23C5 63 patients with a newly diagnosed and pathologically documented bronchogenic carcinoma. Planar dual views of the thorax, abdomen, and brain were acquired between the 24th and 144th hour after the radiotracer injection. Patients had a complete pretreatment workup, which included a routine multiorgan computed tomography (CT) scan, and the determination of the serum and tissue CEA concentration. All patients were followed up clinically and radiologically. Nineteen needle aspirations and biopsies, 23 surgical explorations, and 4 mediastinoscopic studies yielded 121 pathologically documented sites of reference. RESULTS: Fifty-seven of 63 scans were positive for the primary tumor (sensitivity, 0.90). The uptake of the radiotracer correlated significantly with the intensity of tissue CEA expression (Spearman R [Rs], 0.25; P less than 0.05), but not with the serum CEA level or with the histotype. Overall, the sensitivity of the anti-CEA immunoscintigraphy (IS) for the N1, N2, N3, T3, T4, and M1 disease (1987 International Union Against Cancer [UICC] staging classification) was 0.67, 0.64, 0.62, 0.31, 0.29, and 0.86, respectively. Corresponding values of specificity were 0.67, 0.81, 0.90, 1, 1, and 0.93; accuracy values were 0.67, 0.71, 0.85, 0.71, 0.76, and 0.92. The authors limited the analysis to all of the pathologically documented sites and obtained slightly superior values but no meaningful differences. The stage derived from IS readings was correct in 33 patients. The same figure was obtained after an initial clinical workup, which included physical examination, laboratory routine tests, chest radiographs, bronchoscopy, and any diagnostic procedure indicated by those tests. CONCLUSIONS: Anti-CEA FO23C5-F(ab')2 fragments are not yet "magic bullets" for perfect diagnoses; however, their staging potential seems to be remarkable. Technical improvements, single-photo emission CT, and the use of such fragments in combination with other imaging techniques might enable researchers to further improve the current results.

[A study of the variations in myocardial perfusion induced by systemic thrombolysis in acute myocardial infarct using sequential scintigraphy with 201-thallium]. / Studio delle variazioni di perfusione miocardica indotte dalla trombolisi sistemica nell'infarto miocardico acuto mediante scintigrafia sequenziale con tallio 201.

To assess scintigraphic changes induced by intravenous streptokinase therapy, serial rest redistribution thallium-201 perfusion imaging was performed in 62 patients with acute myocardial infarction lasting less than 6 hours. Twenty-seven patients randomized to treatment with intravenous streptokinase (group A) and 35 to conventional therapy (group B) underwent thallium-201 scintigraphy as soon as possible after admission to the coronary care unit (early study). Regional myocardial perfusion was assessed using thallium-201 scintigraphy 7-9 days later in each patient (late study). The size of the perfusion defect was evaluated using a semi-quantitative score. The size of the perfusion defect decreased in serial scans in both group A (preintervention score: 12.1 +/- 6.8; redistribution score: 11.4 +/- 6.8; late study: 8.8 +/- 7.0) and group B (12.8 +/- 6.5; 12.3 +/- 6.7; 10.6 +/- 7.5, respectively). No statistical difference in myocardial perfusion was found between the two groups, on late study. Peak serum creatine kinase MB (CKMB) was earlier in group A than in group B (1030.8 +/- 326.6 vs 1361.0 +/- 271.1: p less than 0.001). The fast CKMB release group (onset of symptoms-peak of CKBM less than or equal to 900 minutes) exhibited higher thallium-201 uptake when compared to the slow CKMB release group, at the time of late study (perfusion defect score: 6.1 +/- 5.7 vs 10.7 +/- 7.3: p = 0.03). Reversibility was observed in 21/62 patients (34%). Reversibility corresponded to unchanged or improved perfusion defect score on late study in 18/21 patients (86%). Nevertheless 20/41 (49%) patients not showing redistribution of thallium-201 within pre-treatment defect had an improvement in regional perfusion on late study. Reversibility was observed in 9/14 (64%) patients with fast CKMB release and in 12/47 (26%) patients with slow CKMB release. We conclude that the early peak of CKMB is associated with a higher uptake of thallium-201 on late study. Furthermore, the reversibility of perfusion defect on redistribution imaging forecasts evolution of scintigraphic perfusion, but, when this is not present, it doesn't rule out late improvement of thallium-201 myocardial uptake. The low sensitivity and specificity of redistribution imaging and the procedure related delay in instituting therapy make thallium-201 scintigraphy unreliable in the evaluation of myocardial reperfusion following thrombolysis.

[Acute cholecystitis. Early diagnostic study using cholescintigraphy with Tc99m-IDA]. / La colecistite acuta. Indagine diagnostica precoce con la colescintigrafia con IDA-99mTc.

34 patients admitted for suspected acute cholecystitis were evaluated using 99mTc IDA cholescintigraphy. The results of these studies are reviewed and compared with other diagnostic tests and the subsequent clinical diagnosis. Cholescintigraphy proved to be a safe, simple, highly accurate and sensitive technique. Therefore, 99mTc-IDA cholescintigraphy is proposed as the initial procedure of choice in the evaluation of patients with suspected acute cholecystitis.

[Heterotopic autotransplant of the spleen after splenectomy in traumatic rupture. Personal experience and scintigraphic follow-up]. / L'autotrapianto eterotopico di milza dopo splenectomia per rottura traumatica. Esperienza personale e follow-up scintigrafico.

Certain aspects of OPSI (Overwhelming Post-Splenectomy Infection) are examined, mainly its considerable gravity, its relatively high incidence, especially in children; its difficult prophylaxis with a report on personal experience of ectopic autotransplant of spleen tissue in two young patients after splenectomy for traumatic rupture. The technique was found to be simple and quickly performed. Scintigraphic follow-up for over 4 years after the operation showed satisfactory growth in the transplanted spleen tissue.